Today Microsoft announced that Windows Phone 8 will support Alipay in China, adding a key payment option to its mobile platform, potentially boosting developer revenues as the number of users in the country that can purchase apps has now risen greatly.

According to Microsoft, Windows Phone 8 in China is “beginning to ramp up,” citing the addition of China Mobile – and its more than 700 million subscribers – as a partner as evidence.

Alipay, which Microsoft likens in functionality to PayPal, the popular online payments processor in the United States and Europe, has more than 800 million registered accounts. This is key as its addition expands the methods that users can pay with away from internationally sourced credit cards. The average smartphone user in China likely lacks such a payment tile, and thus Alipay’s addition will allow them to shop as they wish.

Xbox games have been made available in the Chinese Windows Phone Store.

The addition of Alipay matters as it helps Microsoft improve its pitch one notch more to developers that they not only should develop for its platform to ensure that their users on all platforms are serviced, but also that they can derive meaningful revenues from the mobile operating system.

Microsoft’s decision to directly indicate that its progress in the Chinese market is accelerating is interesting. However, until the company gets off its hands and puts out hard numbers, we refuse to be moved.